NUR612 Pathophysiology Final McCance & Huether (8th ed., 2019)

NUR612 Pathophysiology Final McCance & Huether (8th ed., 2019) It is true that a eukaryotic cell A. is smaller than a prokaryotic cell. B. contains structures called organelles. C. lacks a well-defined nucleus. D. does not contain histones. - ANS B. Contains structures called organelles. Eukaryotic cells contain organelles and histones, they have a well-defined nucleus, and are larger than prokaryotic cells. Ch01.1 The function of a histone found in a eukaryote cell focuses on cellular A. division. B. movement. C. activities. D. deoxyribonucleic acid (DNA) folding. - ANS D. deoxyribonucleic acid (DNA) folding. The histones are binding proteins that cause the supercoiling of DNA into chromosomes and do not affect cellular division, movement, or activities. Ch01.2 An organelle that is responsible for the metabolism of cellular energy is referred to as a/an A. Golgi complex. B. mitochondrion. C. endoplasmic reticulum. D. nucleolus. - ANS B. mitochondrion Mitochondria play a role in cellular metabolism, cellular respiration, and energy production. The Golgi complex is responsible for processing and packaging proteins from the endoplasmic reticulum, where they are synthesized. The nucleolus is a small, dense structure that contains the ribonucleic acid (RNA), DNA, and DNA-binding proteins. Ch01.3 Which statement best describes a desmosome? A. A desmosome is a barrier to diffusion. B. Desmosomes hold cells together by continuous bands. C. A desmosome is a communicating tunnel. D. Desmosomes function as a zona occludens. - ANS B. Desmosomes hold cells together by continuous bands. The desmosome is a type of cell junction. The other two types include tight junctions and gap junctions. Desmosomes hold cells together by forming a continuous band of epithelial tissue or belt (or button-like) points of contact. They are also a source of structural stability. Tight junctions serve as barriers to diffusion and prevent the movement of substances through transport proteins. Gap junctions are clusters of communicating tunnels. Ch01.4 Which statement describes the function of a second messenger? A. Binds with membrane-bound receptors via a ligand B. Triggers a cascade of intracellular events C. Opens specific channels in the cell membrane D. Blocks a membrane-bound receptor signal - ANS B. Triggers a cascade of intracellular events The binding of a ligand to a cell surface receptor triggers the activation of intracellular second messengers. Second messengers activate signal transduction pathways in the cell that can initiate different intracellular events. Cyclic adenosine monophosphate (cAMP) and calcium (Ca++) are the two major second-messenger pathways. First messengers are the extracellular ligands that bind to cell surface receptors. Binding of first messengers can result in the opening or closing of specific cell membrane channels or the activation of second messengers. Ch01.5 Which statement is correct regarding cellular energy? A. Glycolysis is the building of sugar molecules. B. Oxidative cellular metabolism is a single reaction making adenosine triphosphate (ATP). C. Oxidative phosphorylation occurs in the mitochondria. D. Anaerobic glycolysis occurs in the presence of oxygen. - ANS C. Oxidative phosphorylation occurs in the mitochondria. Oxidative phosphorylation occurs in the mitochondria. This is the mechanism by which the energy produced from carbohydrates, fats, and proteins is transferred to ATP. Glycolysis is a process that breaks down glucose molecules; it produces a net of two ATP molecules. Oxidation is a process during which a pair of electrons are removed and transferred. Oxidative cellular metabolism involves 10 biochemical reactions. Anaerobic glycolysis occurs in the absence of oxygen. Aerobic means in the presence of oxygen. Ch01.6 Movement of a solute molecule from an area of high concentration to an area of low concentration is called A. diffusion. B. filtration. C. osmosis. D. hydrostatic pressure. - ANS A. diffusion. Diffusion is the movement of a solute from an area of high concentration to an area of low concentration. Osmosis is the movement of water down a concentration gradient from an area of higher water concentration to an area of lower water concentration. Filtration is the movement of water and solute through a membrane because of a greater pushing pressure on one side of the membrane than the other. Hydrostatic pressure is the mechanical force of water pushing against a cell membrane. Ch01.7 Which is an example of an energy-releasing process? A. Anabolism B. Catabolism C. Substrate-induced reaction D. Second messenger system - ANS B. Catabolism Catabolism is an energy-releasing process. The energy-using process is anabolism. A substrate is a specific substance that is converted to a product in the reaction. A second messenger is a "pass-it-on signal." This occurs when a first messenger activates a receptor that then triggers a pass-it-on signal. Ch01.8 Which describes an amphipathic molecule? A. It is permeable to water only. B. It is a nonpolar molecule. C. It is both hydrophobic and hydrophilic. D. It is a one-layered structure. - ANS C. It is both hydrophobic and hydrophilic. The amphipathic molecule is both hydrophobic and hydrophilic. A hydrophilic molecule is a charged, water-loving molecule. A hydrophobic molecule is an uncharged or water-hating molecule. A polar molecule is another name for an amphipathic molecule. Ch01.9 Which are the roles of relay chains in signal transduction? (Select all that apply.) A. Transfer the signal B. Converge the signal C. Amplify the signal D. Distribute the signal - ANS A. Transfer the signal C. Amplify the signal D. Distribute the signal The functions of relay chains include transferring the signal from its reception point to another part of the cell where it is expected; amplifying the signal received and making it stronger; and distributing the signal so that it influences several processes in parallel. The signal can diverge, not converge, and be relayed to several different intracellular targets. Ch01.10